17:15 〜 18:45
[PPS02-P08] Development of a system for angle of repose measurement with small sample quantities
キーワード：傾斜分布、安息角、帰還サンプル
The current state and historical changes in the small bodies’ surface slope distribution provide insights into the evolutionary history of the small bodies (Miyamoto et al., 2007). Various exploration missions have conducted images and laser altimetry observations on small bodies, leading to constructions of the global and regional Digital Terrain Models (DTM) and gradually revealing the surface slope distribution of the small bodies (Barnouin et al., 2020).
Analyzing how the present state of the surface slope distribution on the small bodies was reached requires consideration of factors such as celestial body gravity, mineral composition and chemical composition, particle size distribution, particle shape, and bulk density of the regolith (Scheeres et al., 2010). While theoretical consideration of these factors is crucial, experimental consideration of regolith’s behavior in bulk with the return samples from exploration missions could provide valuable data that might constrain the behavior of regolith and the variations in the slope distribution on the surface of the small bodies. Notably, experimental studies focusing on the Angle Of Repose (AOR) for the return samples of small body have been lacking. Conventional systems for measuring AOR require sample quantities ranging from tens of grams to several kilograms, exceeding the limited sample amounts available from return samples.
In this research, a developed system capable of measuring AOR with sample quantities around 50 mg will be introduced, and the validity of the system will be discussed . In the case of small sample quantities, it is necessary to reduce the inner diameter of the funnel and the diameter of the base that the pile is formed on. Additionally, the development of a measurement apparatus considers factors such as sample stacking in the funnel and horizonal and vertical alignment between the funnel and the base. The validity of the developed system is evaluated by comparing the AOR for large and small quantities of Phobos simulants.
Reference:
Miyamoto, H., et al., 2007. Science. 316, 1011-1014.
Barnouin, O.S., et al., 2020. Journal of Planetary and Space Science. 180, 104764.
Scheeres, C. M., et al., 2010. Icarus. 210, 968-984.
Analyzing how the present state of the surface slope distribution on the small bodies was reached requires consideration of factors such as celestial body gravity, mineral composition and chemical composition, particle size distribution, particle shape, and bulk density of the regolith (Scheeres et al., 2010). While theoretical consideration of these factors is crucial, experimental consideration of regolith’s behavior in bulk with the return samples from exploration missions could provide valuable data that might constrain the behavior of regolith and the variations in the slope distribution on the surface of the small bodies. Notably, experimental studies focusing on the Angle Of Repose (AOR) for the return samples of small body have been lacking. Conventional systems for measuring AOR require sample quantities ranging from tens of grams to several kilograms, exceeding the limited sample amounts available from return samples.
In this research, a developed system capable of measuring AOR with sample quantities around 50 mg will be introduced, and the validity of the system will be discussed . In the case of small sample quantities, it is necessary to reduce the inner diameter of the funnel and the diameter of the base that the pile is formed on. Additionally, the development of a measurement apparatus considers factors such as sample stacking in the funnel and horizonal and vertical alignment between the funnel and the base. The validity of the developed system is evaluated by comparing the AOR for large and small quantities of Phobos simulants.
Reference:
Miyamoto, H., et al., 2007. Science. 316, 1011-1014.
Barnouin, O.S., et al., 2020. Journal of Planetary and Space Science. 180, 104764.
Scheeres, C. M., et al., 2010. Icarus. 210, 968-984.